Radiological Classification of Congenital Pseudarthrosis of the Tibia

Accepted 7.iii.73 The results of operative treatment of congenital pseudarthrosis of the tibia are difficult to assess.In many cases they seem confusing and actually conflicting.This is due hot only to the small number of cases included in most materials, but also to a heterogeneous definition of the materials and a large number of different therapeutic methods.Moreover, the follow-up period has often been insufficient.Lastly, the general assumption that all cases of congenital tibial pseudarthrosis are alike is presumably not correct (Nicoll 1969).In order to decide whether different types of congenital tibial pseudarthrosis can be distinguished (Andersen 1972) and in order to be better able to assess the results of their operative treatment, I have investigated the possibility of classifying cases of congenital pseudarthrosis of the tibia into radiologically uniform types. M A T E R I A LCongenital pseudarthrosis of the tibia is taken to mean all congenital fractures of the tibia as well as pseudarthroses of thc tibia arising after pathological fracture in a tibia with congenital anterior angulation.Cases in which systemic skeletal diseases have contributed to the occurrence of the fracture or pseudarthrosis were excluded.To obtain an accurate definition of the disease concept, cases arising after osteotomy on a lower leg with congenital anterior angulation were not included.From orthopaedic departments and hospitals in Denmark, Norway, Sweden, and USA, I have collected 60 cases diagnosed as congenital pseudarthrosis of the tibia.For all cases I had access to complete records and X-ray films from the time treatment had been started until it had been completed or until 1970.In 5 cases the fracture was truly congenital.In 8 cases the pseudarthrosis had arisen after osteotomy and in the remaining 47 cases after fracture of the tibia.In the 5 congenital cases there were X-ray films of the affected leg from not later than one week after birth, and in 20 cases in which the pseudarthrosis arose after a fracture X-ray films from before the fracture were available.These 25 cases make up the present material.